ALTER BOY: William McKee goes by “Mandi” these days; he says a baldness treatment made him a gay cross-dresser. Photo:

ALTER BOY: William McKee goes by “Mandi” these days; he says a baldness treatment made him a gay cross-dresser. (
)

This baldness cure was a bust.

For nine months, William McKee took the generic version of Propecia, the pills that promise to halt hair loss.

But the drug had radical side effects: Instead of becoming a better-looking man, he started becoming a woman, he claims.

“My rock-hard chest from the gym began to soften . . . reaching the point where I had noticeable ‘breasts’ even under my clothing,” he says.

Among other changes, the 38-year-old software engineer claims, “my shoulders were literally falling into a more feminine position, and my hips were loosening and becoming wider, as on a woman’s body.”’

McKee, who says he wasn’t inclined to cross-dress before, began feeling like a woman. He is now only attracted to men.

After overcoming depression and separating from his wife of 10 years, McKee goes by “Mandi.” He wears a blond wig, makeup and tight dresses. He plans to get a breast-enhancement job this year, and may undergo sex-change surgery.

“It felt like the ‘me’ that I’ve always known was not there any more,” he told The Post.

Propecia inhibits the conversion of testosterone, resulting in increased estrogen. Millions have used it since the 1990s, but it has been linked to sexual problems such as impotence, loss of libido and “genital shrinkage” as well as cognitive impairment, or “brain fog,” which McKee believes he also suffered.

Lawsuits filed in 27 states by men who say the wonder drug screwed up their sexuality have been centralized in Brooklyn federal court.

A spokesman for Merck, the drug’s maker, said, “No causal relationship has been established between Propecia and persistent sexual side effects.”

McKee, a former Silicon Valley entrepreneur and the father of a 5-year-old son, said he used to be “driven and athletic.” Baldness runs in his family; his hairline began to recede in his 20s.

After seeing Propecia ads for years, he ordered a supply in 2008 from an online pharmacy based in India.

He paid $99.50, including shipping, for pills of the generic finasteride.

He popped one pill a day for nine months. His hair growth was “minimal, if any,” he said, but the feminizing effects were “pronounced.”

“People were kidding me about my breasts,” he said.

His work suffered, too, he said. His last business, Tampa Bay Interactive, went bust in late 2010.

But McKee can’t join the mass lawsuit because the courts bar those who took the generic versions.

In frustration, “Mandi McKee” launched a blog to vent about her life.

Brooklyn attorney Marc Grossman, whose firm represents more than 300 former Propecia users, said many had breast growth.

He also said animal studies on Propecia showed an increased propensity for homosexuality.

Grossman estimates that more than 1,500 Propecia users will come forward but added, “Many men are embarrassed to reveal their problems to anyone, including their doctors, so thousands more will go on living with the condition in private.”